30 research outputs found
Chaotic global parameters correlation with heart rate variability in obese children
The aim of the study is to analyze heart rate dynamics in obese children by measures of HRV. HRV is a simple and non-invasive measure of autonomic impulses. 94 children of mixed gender aged eight to twelve years were divided into two equal groups based on body mass index: obese and normal weight range. HRV was monitored in the dorsal decubitus position for 20 minutes. After tests of normality, Kruskal Wallis was applied for the statistical analysis, with the level of significance set at (p < 0.05). Regarding the application of Principal Component Analysis the first two components represent 99.4% of total variance. The obese children exhibited in heart frequency dynamics associated to an increase in the Chaos Forward Parameter. The Chaos Forward Parameter which applies all three chaotic global parameters is suggested to be the most robust algorithm. Obesity in children can be termed a dynamical condition but it increases the chaotic response
HEART RATE DYNAMICS BY NOVEL CHAOTIC GLOBALS TO HRV IN OBESE YOUTHS
Objective: this study aimed to assess the heart rate dynamics in young obese subjects by novel chaotic globals to HRV. Methods: eighty-six young subjects were distributed in two equal groups (n = 43) according to the nutritional status: obese and control following Body Mass Index. For the analysis of HRV indexes, the heart rate was recorded heartbeat to heartbeat with the young resting in dorsal (prone) position for 30 minutes. Results: after Anderson-Darling and Lilliefors tests, the data was deemed non-normal. So, Kruskal-Wallis test of significance was applied for the statistical analysis, level set at (p < 0.01). Principal Component Analysis (PCA) identified two components represented 100% of total variance. The algorithm which applies all three parameters is suggested as the most influential and statistically very significant at the level (p < 0.001); it also elevates the chaotic response. Conclusion: youth obesity increases the chaotic response. The reasons for the study include quantitative assessment to allow effective dietary, pharmacological or even surgical intervention in the condition
Non-linear regulation of cardiac autonomic modulation in obese youths: Interpolation of ultra-short time series
Background. In this study, we applied ultra-short time series of interbeat intervals (RR-intervals) to evaluate heart rate variability through default chaotic global techniques with the purpose of discriminating obese youths from non-obese youth patients. Method. Chaotic global analysis of the RR-intervals from the electrocardiogram and pre-processing adjustments was undertaken. The effect of cubic spline interpolations was assessed, while the spectral parameters remained fixed. Exactly, 125 RR-intervals of data were recorded. Results. CFP1, CFP3, and CFP6 were the only significant combinations of chaotic globals when the standard conditions were enforced and at the level p<0.01 (or <1%). These significances were acheived via Kruskal–Wallis and Cohen’s ds effects sizes tests of significance after Anderson–Darling and Lilliefors statistical tests indicated non-normal distributions in the majority of cases. Adjustments of the cubic spline interpolation from 1 to 13 Hz were revealed to be inconsequential when measured by Kruskal–Wallis and Cohen’s ds, regarding the outcome between the two datasets. Conclusion. Chaotic global analysis was offered as a robust technique to distinguish autonomic dysfunction in obese youths. It can discriminate the two different groups using ultra-short data lengths, and no cubic spline interpolations need be applied
RISK APPRAISAL BY NOVEL CHAOTIC GLOBALS TO HRV IN SUBJECTS WITH MALNUTRITION
The aim of this study is to assess the risk of dynamical diseases in malnourished children. This is achieved by the application of novel chaotic global techniques to the RR-intervals of the electrocardiogram (ECG) in the cohort. Heart Rate Variability (HRV) is an inexpensive and non-invasive tool to measure the autonomic impulses. Here there has been a decrease in chaotic response of HRV. Seventy children were divided into equal groups and the HRV monitored for 20-25 minutes. The Chaos Forward Parameter (CFP) which applies all three chaotic global parameters is suggested to be the most robust algorithm. These three parameters are high spectral entropy (hsEntropy), high spectral detrended fluctuation analysis (hsDFA) and spectral multi-taper method (sMTM). hsEntropy is a function of the irregularity of amplitude and frequency of the power spectrums peaks. It is derived by applying Shannon entropy to the multi-taper method power spectrum. To derive hsDFA we calculate the spectral adaptation in exactly the same way as for hsEntropy using an adaptive multi-taper method power spectrum with the same settings; but DFA rather than Shannon entropy is the algorithm applied. sMTM is the area between the multi-taper method power spectrum and the baseline. After Anderson-Darling and Lilliefors tests of normality; Kruskal-Wallis was used for the statistical analysis, with the level of significance set at (p < 0.01). Principal Component Analysis (PCA) identified two components representing 100% of total variance. Autonomic imbalance measured as HRV and an increased cardiovascular risk are described for overweight children as well as for malnourished and those with anorexia nervosa. The relationship between malnourishment and complexity measures is useful in the risk assessment of dynamical diseases associated with the condition. This is supportive in treatments, assisting the determination of the level of dietary or pharmacological intervention especially in related dynamical diseases
Complex measurements of heart rate variability in obese youths: Distinguishing autonomic dysfunction
Introduction. Heart rate variability (HRV) can be assessed from RR-intervals. These are derived from an electrocardiographic PQRST-signature and can deviate in a chaotic or irregular manner. In the past, techniques from statistical physics have allowed researchers to study such systems.Objective. This study planned to assess the heart rate dynamics in young obese subjects by nonlinear metrics to heart rate variability. Method. 86 subjects were split equally according to status. Heart rate was recorded with the subjects resting in a dorsal (prone) position for 30 minutes. The complexity of the RR-intervals was assessed by five Entropies, Detrended Fluctuation Analysis, Higuchi and Katz’s fractal dimensions Following inconclusive tests of normality we calculated the One-Way Analysis of Variance, Kruskal-Wallis, and the Effect Sizes by Cohen’s d significances. Results. It was established that Shannon, Renyi and Tsallis Entropies and the Higuchi and Katz’s fractal dimensions could significantly discriminate the two groups. The three entropies were higher in obese youths, suggesting less predictable sets of RR intervals (p<0.0001; d≈1.0). Whilst the Higuchi (p<0.003; d≈0.76) and Katz’s (p≈0.02; d≈0.57) fractal dimensions were lower in obese youths. Conclusion. As with chaotic globals an increase in response was detected by three measures of entropy in young obese. This is counter to the decreasing response detected by fractal dimensions. Chaotic globals and entropies are more dependable than fractal dimensions when assessing the responses to obesity
Lower systolic blood pressure in normotensive subjects is related to better autonomic recovery following exercise
Blood pressure (BP) is a cardiovascular parameter applied to detect cardiovascular risk. Recently, the pre-hypertension state has received greater consideration for prevention strategies. We evaluated autonomic and cardiorespiratory recovery following aerobic exercise in normotensive individuals with different systolic BP (SBP) values. We investigated 30 healthy men aged 18 to 30 years divided into groups according to systolic BP (SBP): G1 (n = 16), resting SBP <110 mmHg and G2 (n = 14), resting SBP between 120–110 mmHg. The groups endured 15 minutes seated at rest, followed by a submaximal aerobic exercise on a treadmill and then remaining seated for 60 minutes also at rest, during recovery from the exercise. Cardiorespiratory parameters and heart rate (HR) variability (HRV) (rMSSD, SD1, HF [ms2]) were evaluated before and during recovery from exercise. G2 displayed slower return of SBP, rMSSD and SD1 HRV indices during recovery from exercise compared to G1. In conclusion, normotensive subjects with higher resting SBP (110 to 120 mmHg) offered delayed autonomic recovery following moderate exercise. We suggest that this group may be less physiologically optimized leading to cardiac risks
Waist-stature ratio and its relationship with autonomic recovery from aerobic exercise In healthy men
Autonomic modulation and cardiorespiratory variables are influenced by numerous factors, including anthropometric variables. We investigated autonomic recovery following aerobic exercise in healthy men with different waist-stature ratio (WSR) values. The study was conducted with 52 healthy men aged 18 to 30 years, divided into groups according to the WSR: G1 – between 0.40 and 0.449 (N = 19), G2 – between 0.45 and 0.50 (N = 28) and G3 – between 0.5 and 0.56 (N = 5). The subjects endured 15 minutes seated and at rest followed by an aerobic exercise and then remained seated for 60 minutes and at rest during recovery from exercise. Heart rate (HR) variability (HRV) (rMSSD, SD1, HF [ms2]) and cardiorespiratory variables were analyzed before and after exercise. Recovery of respiratory rate, diastolic blood pressure, SD1 and HF indices were delayed in G2. G3 presented delayed recovery after the maximal effort test while no difference with G2 was noted in the moderate intensity. Correlation and linear regression analysis indicated association of WSR, body mass index and waist circumference with HRV indices in the recovery from aerobic exercise (45 to 60 minutes after exercise) in G2. In conclusion, healthy men with higher WSR accomplished delayed autonomic recovery following maximal effort exercise
Hydatidiform mole resulting from sexual violence
<p>Abstract</p> <p>Background</p> <p>Hydatidiform mole (HM) is characterized by abnormal proliferation of human trophoblast with producers functioning tissues of human chorionic gonadotropin. It can evolve with ovarian cysts tecaluteínicos, hypertension of pregnancy or hyperthyroidism. The incidence of HM is variable and its etiology poorly known, associated with nutritional factors, environmental, age, parity, history of HM, oral contraceptives, smoking, consanguinity or defects in germ cells. There is no reference in literature on HM resulting from sexual violence, objective of this report.</p> <p>Method</p> <p>Description of two cases of HM among 1146 patients with pregnancy resulting from sexual violence treated at Hospital Pérola Byington, São Paulo, from July 1994 to August 2011.</p> <p>Results</p> <p>The cases affected young, white, unmarried, low educated and low parity women. Sexual violence was perpetrated by known offenders unrelated to the victims, under death threat. Ultrasound and CT of the pelvis showed bulky uterus compatible with HM without myometrial invasion. One case was associated with theca lutein cysts. The two cases were diagnosed in the second trimester of pregnancy and evolved with hyperthyroidism. There was no hypertension, disease recurrence, metastasis or sexually transmitted infection.</p> <p>Conclusion</p> <p>The incidence of HM was 1:573 pregnancies resulting from rape, within the range estimated for Latin American countries. Trophoblastic material can be preserved to identify the violence perpetrator, considering only the paternal HM chromosomes. History of sexual violence should be investigated in cases of HM in the first half of adolescence and women in a vulnerable condition.</p
Entropic analysis of HRV in obese children
The aim of the study was to analyze heart rate dynamics in obese children by functional entropic measures of Heart Rate Variability (HRV). HRV is a simple, reliable, cheap and non-invasive measure of autonomic impulses. We applied five technques based on entropy to assess the level of complexity. These were Shannon, Multiscale Tsallis and Multiscale Rényi entropies. Then, Approximate and Sample entropies. Ninety-four children of mixed gender aged eight to twelve years were divided into two equal groups (n=47) based on body mass index: obese and non-obese weight ranges. HRV was monitored in the dorsal decubitus position for 20 minutes. After Anderson-Darling and Ryan-Joiner tests of normality, the parametric test ANOVA1 was applied for the statistical analysis, with the level of significance set at (p<0.05); so the probability of a type I error was less than 5%. All types of functional entropies were significant at that level with the exception of Sample entropy. Furthermore, for all five measures the chaotic response increased when undergoing change from non-obese to obese. Regarding the application of Principal Component Analysis (PCA) the first two components represent 98.9% of total variance; a steep scree plot. The Multiscale Rényi (α=0.25), Shannon and Multiscale Tsallis (q=0.25) entropies performed simlarly regarding PCA and ANOVA1; whilst the Approximate and Sample entropies were also analogous with respect to these particular statisical tests. The Approximate entropy performed the most strongly with respect to p-value (p=0.0092) by ANOVA1 and PCA. With the exception of Sample entropy the entropic techniques described here were able to significantly quantify the increase in chaotic response when non-obese to obese children were assessed by the HRV.
Characteristics and associated factors with sports injuries among children and adolescents
BACKGROUND: The participation of children and adolescents in sports is becoming increasingly common, and this increased involvement raises concerns about the occurrence of sports injuries. OBJECTIVES: To characterize the sports injuries and verify the associated factors with injuries in children and adolescents. METHOD: Retrospective, epidemiological study. One thousand three hundred and eleven children and adolescents up to 18 years of age enrolled in a sports initiation school in the city of Presidente Prudente, State of São Paulo, Brazil. A reported condition inquiry in interview form was used to obtain personal data and information on training and sports injuries in the last 12 months. Injury was considered any physical complaint resulting from training and/or competition that limited the participation of the individual for at least one day, regardless of the need for medical care. RESULTS: The injury rate per 1000 hours of exposure was 1.20 among the children and 1.30 among the adolescents. Age, anthropometric data, and training characteristics only differed with regard to the presence or absence of injuries among the adolescents. The most commonly reported characteristics involving injuries in both the children and adolescents were the lower limbs, training, non-contact mechanism, mild injury, asymptomatic return to activities, and absence of recurrence. CONCLUSIONS: The injury rate per 1000 hours of exposure was similar among children and adolescents. Nevertheless, some peculiarities among adolescents were observed with greater values for weight, height, duration of training, and weekly hours of practice.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES